This invention is an improvement to the debarking/delimbing apparatus of the commonly assigned U.S. Pat. Nos. 4,719,950, 4,721,139 and 4,729,415.
Skidders are a commonly used tractor-like vehicle that is very maneuverable and has a rear mounted grapple. They are used to grab onto the butt ends of felled trees (tree stems) and drag the tree stems (often a bundle of small sized tree stems) from a location in the woods where the trees have been felled to a designated in-field base site. A bundle may consist of one or two to eight or ten tree stems ranging in size from about four inches to about twenty inches in diameter. The bundles of tree stems are hauled through the woods a short distance to the site which will often include a portable tree stem processing apparatus for partially processing the stems. This base site and the portable apparatus are moved from time to time as required by the progress of the logging operation.
A number of processing steps may take place with the portable stem processing apparatus. In one example, tree stems are debarked and/or delimbed by a debarking/delimbing apparatus. Such delimbing apparatus have an inlet including guide roller for guiding the tree stems, butt end first, into and through the apparatus wherein flails beat against the stems to tear off the limbs and/or remove the bark. The debarked and/or delimbed stems are then loaded onto trucks for hauling to a permanently-sited stem processing mill or in some cases, they are further processed in the field as by feeding the stems into a chipper to be used for pulp wood.
The present invention is concerned with the manner of debarking/delimbing the tree stems with a portable debarking/delimbing apparatus. Presently the skidder or skidder-like apparatus simply stacks the tree stems at a location convenient to the apparatus. The stems must be regrappled by a boom mounted grapple, inwardly from the butt end, and fed butt end first into the inlet of the debarking/delimbing apparatus. As the guide rollers and flails of the apparatus take control over the stems, the grapple releases that bundle and returns for a second bundle. The tree stems that emerge from the debarking/delimbing apparatus must again be handled a third time, e.g. for truck loading, stacking or chipping.